The aim of the proposed research is to design, develop and test the in-vivo biologically active collagen based coil for embolizing cerebral aneurysm by improving the overall design and quality of the prototype achieved in the Phase I. Specifically, the investigators propose to design and fabricate an improved collagen coil prototype such that it will be suitable for in-vivo investigations. They also will develop low profile delivery system as a micro catheter of 3 French or smaller with a visibility provided under fluoroscopy. Finally, they would conduct an in-vivo test in rabbits and perform angiographic and histological analyses to test the effectiveness of the collagen coil in inducing occlusion thrombus organization, fibrosis and neo intima formation in the aneurysm. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE